Capacitive detection device utilizing trapezoidal subshape

Patent metadata

Field	Value
Publication number	US-12481408-B2
Application number	US-202519019528-A
Country	US
Kind code	B2
Filing date	Jan 14, 2025
Priority date	Jan 16, 2024
Publication date	Nov 25, 2025
Grant date	Nov 25, 2025

Abstract

The present invention relates to a capacitive touch input device utilizing the capacitive sensing method for detecting touch inputs from a finger or a similar conductive object. More specifically, it pertains to a capacitance detection device designed to facilitate the detection of touch coordinates based on the vertical movement of a pen by employing a capacitive detection sensor composed of a composite trapezoidal shape.

First claim

What is claimed is:

1 . A capacitive detection device comprising:
a primary shape capacitive detection Area (CDA) configured to form an object capacitance with an object positioned vertically opposite thereto and installed on the upper side of a display device; a detection sensor comprising a CDA signal line connected to the primary shape capacitive detection area; a Touch Drive IC (TDI) configured to detect the object capacitance formed in the primary shape capacitive detection area; a CDA column in a coplanar arrangement, configured such that a plurality of the detection sensors are vertically stacked, wherein the number of CDA signal lines increases in proportion to the number of detection sensors stacked from a far distance to a near distance relative to the position of the TDI, and the area of the detection sensors gradually decreases from the far distance to the near distance; and a secondary shape capacitive detection area comprising a composite trapezoidal shape formed by combining two trapezoidal shapes, wherein the primary shape capacitive detection area is formed by interconnecting a plurality of the secondary shape capacitive detection areas, and heterogeneous secondary shape capacitive detection areas are disposed vertically adjacent to each other in the CDA column with a predetermined interval, and wherein the capacitive detection device further comprises: a bundle of signal lines formed by the plurality of CDA signal lines constituting the CDA column; a first voltage forcing line (VFL), located at the (n−1)th position adjacent to one side of a sensing signal line (SSL) and configured to receive an alternating voltage, or a second VFL located at the (n+1)th position adjacent to the other side of the SSL and configured to receive an alternating voltage, when an arbitrary nth CDA signal line in the bundle of signal lines is the sensing signal line; a coplanar capacitor formed between the SSL and the first VFL or between the SSL and the second VFL, wherein each VFL adjacent to the SSL has the same or different line width, separation distance, and facing length, forming a parallel-plate coplanar structure; and a plurality of capacitors having one end connected to the SSL, wherein a charge-sharing phenomenon occurs between the coplanar capacitor and a plurality of capacitors having one end connected to the SSL, driven by charges supplied by the coplanar capacitor, and wherein based on the charge-sharing phenomenon, the object capacitance is detected as a voltage signal at the SSL, further comprising a signal processing unit.

2 . The capacitive detection device of claim 1 , wherein:
when the object moves vertically, including across a boundary line between the heterogeneous secondary shape capacitive detection areas that are vertically separated, vertical touch coordinates are detected based on the area occupancy difference between the secondary shape capacitive detection areas positioned above and below.

3 . The capacitive detection device of claim 1 , wherein;
the coplanar capacitance ccpl(a) formed between the SSL and either the first VFL or the second VFL is determined by the following [Equation 1],

ccpl
⁢

(
a
)

=

ϵ
⁢
r
*

l
⁡
(
a
)

377
⁢
πυ
⁢
0

*

ln

[

-
2

⁢

(

k
+
1

)

k
-
1

]

⁢

(
F
)

[

Equation
⁢

1

]

where
:

a
)

⁢

k

=

⌈

1
-

(

d
⁡
(
a
)

d
⁡
(
a
)

+

2
⁢

w
⁡
(
a
)

)

2

⌉

0.25

;

b) w(a) is the line width of the SSL and either the first VFL or the second VFL;
c) d(a) is the separation distance between the SSL and either the first VFL or the seco nd VFL;
d) l(a) is the facing length between the SSL and either the first VFL or the second VF L at the separation distance d(a);

Assignees

• Lee Sung Ho

Inventors

• Lee Sung Ho

Classifications

• G06F3/04164

  Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads · CPC title

• G06F3/0441

  using active external devices, e.g. active pens, for receiving changes in electrical potential transmitted by the digitiser, e.g. tablet driving signals · CPC title

• G06F2203/04107

  Shielding in digitiser, i.e. guard or shielding arrangements, mostly for capacitive touchscreens, e.g. driven shields, driven grounds · CPC title

• G06F3/0445

  using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer · CPC title

• G06F3/0446

  using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes · CPC title